Change option::t to option

Now that core exports "option" as a synonym for option::t, search-and-
replace option::t with option.

The only place that still refers to option::t are the modules in libcore
that use option, because fixing this requires a new snapshot
(forthcoming).

src/libstd/linux_os.rs

@@ -123,7 +123,7 @@ fn dylib_filename(base: str) -> str { ret "lib" + base + ".so"; }
 
 /// Returns the directory containing the running program
 /// followed by a path separator
-fn get_exe_path() -> option::t<fs::path> {
+fn get_exe_path() -> option<fs::path> {
     let bufsize = 1023u;
     // FIXME: path "strings" will likely need fixing...
     let path = str::from_bytes(vec::init_elt(bufsize, 0u8));